What are the most important scholarly resources for Latin and Greek historical linguistics?

Question

When it comes to historical linguistics (history, prehistory, Indo-European studies, etymology) of Latin and Greek, what are the most important resources? The resources can be historical grammars, etymological dictionaries, or anything similar. I am not looking for a full bibliography, but useful reference material.

When you suggest a source, please indicate how it is available (online, in print, free, paid), what it covers, and what makes it useful in your opinion.

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Answer 1

De Vaan's Etymological Dictionary of Latin is perhaps the most up to date one. He also bases his articles on the other main etymological dictionaries, like Walde-Hofmann and Ernout-Meillet. Sometimes I would have liked his articles to be a bit more expansive, but that would have required a lot more time to write. It is available on paper and online.

Answer 2

Michael Weiss's Outline of the Historical and Comparative Grammar of Latin is the most comprehensive, well-researched, and balanced historical grammar of Latin. There is a website with addenda and corrigenda maintained by the author. It is available on paper only; the second, corrected printing was released in 2011.

Answer 3

For Greek, the best etymological dictionary is Robert Beekes' Etymological Dictionary of Greek in two volumes. This is to Greek what De Vaan is to Latin.

Greek is among the most intensely and widely studied languages known. Since the publication of the last etymological dictionary of Greek, both the reconstruction of Proto-Indo-European, and our knowledge of the Greek substrate have led to numerous, often surprising new insights into the history and formation of the Greek vocabulary. This dictionary is a treasure trove covering 2000 years of Ancient Greek: from Mycenaean via Homer and the classical period to lexicographers, such as Hesychius (5th century A.D.).

It consists of 7500 entries with thoroughly revised etymologies. Each entry gives clear information about the origin of the Greek word and its first date of attestation. It further provides all etymologically relevant variants, dialectal forms, derivatives, compounds, and bibliographical references. This dictionary is a truly indispensable tool for those in search of a deeper knowledge of the Greek vocabulary, its history and, therewith, a better understanding of the language.

As with De Vaan, it is also available in a paperback version.